New University of Colorado Boulder research has addressed the age-old question of why our blood vessels thicken as we age. —the answer is in your gut.
“This is the first study to show that changes in the gut microbiome with aging have an adverse impact on vascular health,” lead writer Vienna Brunt said, (a postdoctoral researcher in the Department of Integrative Physiology.
For this research, researchers gave little mice and older mice, broad-spectrum antibiotics to finish off the bulk of bacteria existing in their gut (gut microbiome). They then evaluated the fitness of their vascular endothelium (inner lining the blood vessels) and the thickness of their arteries.
After a few weeks of the treatment, the younger mice suffered no change in vascular health.
The older ones, however, experienced vast improvements.
“When you suppressed the microbiome of the old mice, their vascular health was restored to that of young mice,” says senior author and professor Doug Seals, (director of the Integrative Physiology of Aging Laboratory). “There is something about those microorganisms that are causing vascular dysfunction.”
To discover what that may be, the team then took fecal samples from a different set of mice and sequenced them genetically, contrasting the gut bacteria of old mice with that of the young.
Example: the old mice contained more Proteobacteria,( phyla that includes Salmonella and other pathogens), and pro-inflammatory Desulfovibrio.
At about 45, the threat of cardiovascular disease starts to sneak up, according to the American Heart Association. By 60–79, 70% of the population of the US have it. After 80, less than one fifth are free of it.
“We have long known that oxidative stress and inflammation are involved in making arteries unhealthy over time, but we didn’t know why arteries begin to get inflamed and stressed. Something is triggering this,” stated Seals. “we suspect, with age, the gut microbiota begins producing toxic molecules, including TMAO, which causes inflammation, oxidative stress and damage tissue.”
They think that diets high in probiotic-rich cultured food (yogurt, kefir) and prebiotic fiber may contribute to preventing heart disease by encouraging a healthy gut microbiome.
They’re studying a compound called dimethyl butanol, found in some olive oils and vinegar, which hinders the bacterial enzyme necessary to produce TMAO which could be used as a dietary supplement.
The authors very wisely say:
“The fountain of youth may actually lie in the gut.”